[noun] + なりに + [verb] [noun] + なりの + [noun] [na-adj] + なりに [i-adj] + なりに [verb (plain)] + なりに
なりに means "in one's own way", "as far as one's position allows"; なりの does the same job in front of a noun. Both follow a noun directly – very often a person, as in わたくし私なりに or こども子供なりの.
The noun names a limit – a child, an amateur, someone new – and the sentence says that within that limit the effort or the result is fair. The pattern defends or accepts; it doesn't belittle.
After an adjective or a plain-form verb, なりに means "for all that it's X, in a way that fits X". A な-adjective takes it directly.
These go beyond a person + なりに.
Repeating the person stresses that they have their own side of things too.